Manufacture and production of artificial filaments, threads, and the like



JulyZl, 1942. R. L. WORMELL 2,290,789

MANUFACTURE AND PRODUCTION OF ARTIFICIAL FILAMENTS', THREADS, AND THE LIKE Filed Nov. 14, 1938 //VV/V70/P ROBERT LOUI'ISY WORMELL v AVTOF/Vf):

Patented July 21, 1942 s mmm MANUFACTURE AND PRonUc'rIo oF-ARTI- FICIAL Robert Louis 'Wo rmell, coventryilylnglandi-assign- Limited, London, England, a

v r to ou a' ds. eBi w l i iApplication'November m, 1938; Serial No; 2 i0,427 g v In Great Britain November 18, 19311 EILAMENTS; 'rnaE ns, v AND THE} 1 I'Claim. (cl; 1s-"-54) This invention relates to the manufacture and I production of threads and the like from icasein,

or protein compounds having similar properties. Within the term threads and thelike- I wish to include filaments, fibres, yarns and threads of any denier or cross-sectional shapeand bands or tows consisting of any-number. of such'filamentary articles. example, by extruding a solution of a protein through one or more jetseach provided with one or more holes and setting the extruded material in any known manner. Each jet may extrude one or a plurality of filaments. If more 3 than one filament is extruded from a jetitney are usually formed into a single thread. 'Any formaldehyde and, aluminium salts, and" which renders the thread more resistant to the dismtegrating, dissolving or swelling action of water or aqueous solutions and improves the properties of the thread finally obtained; A process is also already known wherein casein fibres 'are drawn with a speed which is higher, for example 50 per cent higher, than that of spinning and are conveyed under tension through one or more baths of such hardening agents.

According to the present invention the process for improving the properties of threads and the like produced from casein or the like protein substances and hardened,- comprises stretching them and thereafter treating them with a hardening agent without allowing them to contract.

They; may be; produced for w an aqueoussolution; Aqueous solutions of the lower fatty acids are'particularly suitable; and

thesame-solu'tion as thatuse'dfor hardening may also be used: Stretching should preferably be sufficient to effect an appreciable-"reduction in the denier of the thread and may be for'example,' betweenb'll and 200 percent.

It may be 1 carried outby passljngfthe thread over two or *morerotating rollers'the second and succeeding ones of which are rotated with peripheral speeds greaterthan'that of the first."

' a Treatment with the' hardening agent may be "effected bypassing the thread through an atmosphere containing a hardening agent,'for exampleyformaldehyde in vapour form. It may also be effectedby passing the thread through a" solution contain'ing one orv more hardening agents, as for example natural or synthetic tanning agentsgformaldehyde or aluminium salts The threads may have been produced from casein in any known manner and besideshaving been subjected to a hardening treatment mayv 1 outsome time afterwards. It is very desirable in both cases to effect the stretching in the presence of a'wetting agent, for example water or Other substances may also be added to the hardening bath for other purposes, for example, acetone or alcohol for lowering the specific gravity thereof, or salts such as calcium chloride or sodiumfsulphate for preventing swelling of the threads.

The treatment with a hardening agent after the stretching may or may not result in the complete insolubilisation of the threads, but in any case must be sufllcient to minimise consid erably the contraction of the stretched threads when released from tension. If insolubilisation is not complete after leaving the said hardening bath it may be completed at a later stage ,as desired.

The threads may be dried while in the; retched condition before passing to the said tatment with the hardening agent. .1 .The threads may bejprevented from contracting after stretching by maintaining thestretched condition by mechanical means; for example the threads may be drawn through thehardening bath at the same speed as they leave the stretching device, or they may be simply wound on reels or bobbins after they have been saturated with hardening liquid. Alternatively contraction may be largely prevented by carryin out the hardening-c treatment in the presence of which maybe normal or basicsalts.

" "A suitable solution solution has the followin composition? i Parts Aluminium acetate 10 Formaldehyde x 10 Water F a salt or salts such, for example, as calcium chicride or sodium sulphate.

The threads after treatment according to the present invention may be collected in "the form, for example, of a cake orbobbin, or they may be cut into staple fibres. In the latter'case, cutting may take place either after complete hardento effect although the invention is not restricted to the form of apparatus shown.

ing, washing and drying of the'thr'eads, 'or immediately after they have left the hardening bath in which case the cut threads may need to be left in the wet state for a suitable period Casein solution is extruded through a nozzle I into a bath of coagulant 2 and the resulting thread} is passed over the guide 4 round rollers -5'and 6 which are rotating at equal speeds and are 'paIrtiallyimmersed in a bath containing hardening liquid 1. On leaving the roller 6 the thread 7 is passed two; or three times round a roller 8 until hardening is completed, after which-they can be finally washed and dried.

The following example illustrates one method of carrying out the present invention although the invention is not restricted to this example.

Example Casein threads of denier 2400 containing 600 filaments are drawn off by godets from a coagulating bath containing salts and acid. The threads are passed for minutes through a. hardening bath consisting of 10 per cent aluminium acetate solution and 10 per cent'form aldehyde. The yarn on leaving this apparatus and thence to the roller 9. After passing two to three times round the roller 9 it is passed round the rollers l9 and II to a collectingreel is then passed through a bath of per cent formic acid, in which it"is stretch-ed 100 per cent by means of conical godets grooved in steps. Thereafter, while still under tension, it passes through another bath containing the 10 per cent aluminium acetate-10 per ceiitjormaldehyde mixture, and is then wound up on a drum, The yarn after being left on the drum for 15 minutes is cut oil and immersed in a bath containing formaldehyde, sodium sulphate and aluminium sulphate at centigrade for 24 hours. It is subsequently immersed in the same mixture at 45 centigrade for 48 hours and is thereafter washed thoroughly in water and dried.

I2; Roller I rotates at substantially the same 7 speed as 5 and i and roller 9 at a considerably greater speed while rollers I0 and II, which are partly immersed in a bath containing hardening liquid 13, both rotate'at substantially the same speedas the roller 1. In this case after leaving the coagulating bath the thread is subjected to a hardening treatment without stretching in the bath 1. It is then stretched between the rollers 8 and Sand is-then finally hardened without stretching in thebath l3.

' What I claim is:

' A process for the manufacture and production of threads and the like, which comprises extruding a solution containing casein into a coagulating medium; drawing on. filaments from said coagulating medium and subjecting them to a preliminary hardening treatment, and thereafter improving the properties'ofthe thread by stretchingthem and then subjecting them to a second hardening treatment without allowing them to contract. 

